Bumper device



Dec. 27, 1966 R. B. DE MENT 3,294,254

BUMPER DEVICE Filed June 17, 1964 ROBERT B. De MENT ATTORNEY United States Patent O This invention relates to an overhead crane structure and more particularly to a bumper device used on an overhead crane.

In conventional types of overhead cranes, the crane is l advanced along a track or tracks, as the case may be, to move suspended material supported on the crane. At the ends of the tracks there is normally an abutment positioned to contact the supporting structure of the crane so as to check or stop the advance. A bumper may be used to soften the blow of impact with the abutment.

In overhead cranes the tracks are normally high and diicult, if not dangerous, to reach, Consequently the number of times it is necessary to replace or maintain the bumper is of primary importance.

With the aibove in mind, it is the primary purpose of the present invention to provide a new and novel type of bumper device capable of withstanding large shock loads as well as a large number of shock cycles` In many bumper guards for cranes, the means of attaching the guard to the crane often fails before the guard fails. This may occur by shearing connecting studs mounting the guard on the crane structure. Often vibration, caused by large numbers of impacts, will cause threaded connections to become loosened and eventually the entire bumper device to fail.

It is therefore a further object of the invention to provide in the bumper device a thin wafer of resilient material between the base plate of the bumper and supporting structure for the bumper which operates to cushion and dampen the effects of impacts and vibrations on the bumper device.

It is still a further object of the invention to provide a new and novel method of making a bumper device that utilizes placing a cylinder or hollow pipe over a base plate with openings therethrough, filling the pipe with an uncured compound, and heating the entire assemblage until the compound becomes highly viscous and flows through the openings to form a thin wafer-like portion beneath the base plate.

Other objects and advantages of the invention will become apparent to those skilled in the art as the invention is better understood from the following description and as shown in the accompanying drawings.

FIG. 1 is a side view of a portion of the crane carriage and a portion of the supporting track and showing the structure of the present invention.

. FIG. 2 is an enlarged end view of the bu-mper structure shown in FIG. 1.

FIG. 3 is a sectional view of the bumper device taken substantially along the line 3-3 of FIG. 2.

FIG. 4 is a vertical sectional view through the molding form and base plate as viewed during preparation of making the bumper device.

FIG. 5 is a side View of the bumper device following curing of the elastomeric material.

A crane, not shown, is supported on a crane supporting carriage or structure 10, having a guide wheel 11 rotatably carried on a short shaft 12 and adapted to advance along a track 13. The track 13 may be of any conventional design and anchored at opposite ends on wall structures, as indicated at 16. In order to limit advance of the crane carriage 10, so as to not contact the wall 16, there is fixed to the wall 16 an abutment structure 14 overlying the end of the track 13. The abutment structure 14 has Patented Dec. 27, 1966 ICC an upper abutment portion 15 with a striking plate 17. The plate 17 is horizontally alined with an upright bumper carrying plate 18 carried in advanced relation on the crane carriage 10. The plate 18 has fixed thereto by small taps or |bolts 19 a bumper device, indicated in its entirety by the reference numeral 20.

The bum-per device 20 is composed of a flat upright base plate 21 having an outer surface 22 facing the abutment 14 and an inner surface 23 closely adjacent the support plate 18. A plurality of frusta-conical shaped holes or openings 24 are provided in the plate 21 and have their small ends opening to the surface 22 and their large ends opening to the surface 23. Also provided in the plate 21 are four marginal holes 25 adjacent the respective corners of the plate 21 that receive the connectors or bolts 19.

Bonded to the surface 22 of the plate 21 is an abutment member or column 30 of elastomeric material. The column 30 is circular in cross section and projects in advance horizontal relation tol the plate 21. Adjacent its juncture withthe surface 22 the column 30 has small radially outwardly projecting taper 32 serving to increase the strength of the bonding. The column 30 is generally vertical and flat at its free or outer end 31. As is clearly apparent from viewing FIG. 1 the free end 31 normally contacts the striking plate 17.

The opposite end of the flexible abutment member 30 has anchoring studs 35 extending through the plate 21 via the holes 24. The abutment member 30 further has yan integral thin wafer-like cushion 33 bonded to the sul'- face 23 and having rather uneven edges 34, for reasons later to become apparent, extending close to the outer edges of the base plate 21. The small frusto-conical shaped studs 35 as well as the wafer portion 33 afford a mechanical connection that reinforces the chemical bonding of the column 30 to the surface 22. Actually, therefore, the column 30 is supported on the plate 21 by both mechanical means and chemical bonding.

The small wafer-like portion 33 further operates as a cushion between the two plates 18, 21 and generally dampens the shock of contact so that the bolts 19 do not loosen or/and shear due to numerous impacts on the bumper device 20.

Considered unique is the manner of producing the bumper device, and such is shown in FIGS. 4 and 5. The bumper device is made in an upright disposition and is formed by placing the base plate 21 on a flat horizontal surface 40 which may be the top surface of a metal plate or pan adapted for insertion in an oven. An upright metal cylinder or pipe 41 is laid upright above and on the base plate 21 with its lower annular edge 42 circumscribing the three tapered holes 24. An bonding cement is applied to the surface 22 of the plate 21. The cylinder 41 has an internal beveled lower edge 43 that forms the beveled Vshould be recognized the openings 24 are centrally located and equally spaced about the actual center of the plate 21 so as to permit a relatively even flow in all directions between the surface 40 and the plate 21 when the wafer portion 33 is being formed.

While only one form of the invention has been shown, it is recognized that other forms and variations will occur to those skilled in the art. Therefore it is to be understood the preferred form was shown and described in detailed manner for the purpose of clearly and concisely illustrating the principles of the invention, and it was not the intention to narrow or limit the invention beyond the broad concept set forth in the appended claims.

What is claimed is:

1. A bumper device for use with a crane having structure adapted to advance along a track, the track having an abutment for limiting advancement of the structure and the structure having a rigid upright portion aligned with the abutment, the bumper device comprising: an upright base plate having .a iirst side facing the structure and a second side facing the abutment and a plurality of tapered openings extending therethrough and tapered from small ends at the second side to relatively large ends at the first side; a flexible bumper of elastomeric material having an abutment portion projecting in advance of and from the second side and bonded to its surface, a wafer portion bonded to the first side, and tapered anchoring studs of the elastomeric material disposed in the openings integral with and interjoining the wafer portion and abutment portion; and marginal holes in the plate adapted to pass connector elements for fixing the device to the structure.

2. A bumper device for use with a crane having structure adapted to advance along a track, the track having an abutment for limiting advancement of the structure and the structure having a rigid upright portion aligned with the abutment, the bumper device comprising: an upright base plate having la first side facing the structure and a second side facing the abutment and a tapered opening extending therethrough and tapered from a small end at the second side to a relatively large end at the first side; a fiexible bumper of elastomeric material having an abutment portion projecting in advance of and from the second side and bonded to its surface, a wafer portion on the first side, and a tapered anchoring stud of the elastomeric material disposed in the opening integral with the interjoining the wafer portion and abutment portion; and marginal holes in the plate adapted to pass connector elements for fixing the device to the structure.

3. A bumper device comprising: a base plate having first and second sides and a plurality of tapered openings extending therethrough and tapered from small ends at the second side to relatively large ends at the first side; a flexible bumper of elastomeric material having an abutment portion projecting from the second side and bonded to its surface, a thin wafer portion on the rst side, and tapered anchoring studs of the elastomeric material disposed in the openings integral with and interjoining the wafer portion `and abutment portion; and a means on the plate adapted to x the device to a supporting structure.

4. A bumper assembly including an upright bumper supporting member with an upright face; an upright base plate having a first side adjacent and facing the face and a second side facing away from the member and a plurality of .tapered openings extending therethrough and tapered from small ends at the second side to relatively large ends at the first side; a fiexible bumper of elastomeric material having an abutment portion projecting from the second side and bonded to its surface, a thin wafer portion on the first side between the latter and the member, and tapered anchoring studs of the elastomeric material disposed in the openings integral with and interjoining the wafer portion and abutment portion; and means on the plate adapted to fix the plate to the member whereby the wafer portion is in contact with the surface and effects a c-ushion between the plate and member.

5. A bumper assembly including an upright bumper supporting member with an upright face; an upright base .plate having a first side adjacent and facing the face and -a second side facing away from the member, and an opening therethrough; a liexible bumper of elastomeric material having an abutment portion projecting from the second side and bonded to its surface, a thin Wafer portion on the first side between the latter and the member, and a portion of elastomeric material disposed in the opening integral with and interjoining the wafer portion and abutment portion; and means on the plate adapted to fix the plate to the member whereby the wafer portion is in contact with the surface and effects a cushion between the plate and member.

6. A bumper device comprising: a base plate having first and second sides and an outer peripheral edge, the plate having holes adjacent the edge for receiving attachment elements and a plurality of tapered openings adjacent the center of the plate extending therethrough and tapered from small ends at the second side to relatively large ends at the first side; and a flexible bumper of elastomeric material having an abutment portion projecting from the second side and bonded to its surface, a wafer portion on the first side extending .adjacent the peripheral edge, and tapered anchoring studs of the elastomeric material disposed in the openings integral with and interjoining the wafer portion and abutment portion.

7. The invention defined in claim 6in which the Iabutment portion is round in cross section and further characterized by having an .annular taper extending radially outwardly at its juncture with the plate.

8. A method of making a bumper device comprising: placing a base plate having a plurality of tapered holes cna horizontal surface with the large ends of the holes facing downwardly; placing an annular edge of a cylindrical shaped metal form on the base in a circumscribed relation to the holes; placing a bonding cement on the upper surface of the plate; filling the cylindrical form with an uncured elastomeric compound; heating the entire assemblage to sufficient temperature to fluidize the compound to effect ow thereof through the holes and between the underside of the plate and the horizontal surface while curing the compound to thereby form a thin waferlike layer of elastomeric material on the underside of the plate.

'9. A method o-f making a bumper device comprising: placing a base plate having a plurality -of tapered holes on a horizontal surface with the large ends of the holes facing downwardly; placing the lower edge of an upright tubular form on the base plate in a circumscribed relation to the holes; filling the form with an uncured elastomeric compound; heating the assemblage to sufficient temperature to uidize the compound to effect flow of part thereof through the holes and between the underside of the plate and the horizontal surface while curing the compound to thereby form a thin wafer-like layer of elastomeric material on the underside of the plate.

References Cited by the Examiner UNITED STATES PATENTS 641,602 1/ 1900 McGunningle 152-384 1,024,189 4/ 1912 Dow 152-323 1,201,206 10/ 1916 Lewis 104-149 1,544,639 7/1925 Fowler 152-310 1,832,184 11/ 193 1 Christen.

1,866,797 7/ 1932 Burdette 152-323 2,144,357 1/ 1939 Booharin 267-1 2,706,113 4/ 1955 Hickman 267-21 2,770,868 11/ 1956 Streckfus et al. 152-323 X 2,986,419 5/ 1961 Barenyi 293-62 3,073,260 1/ 1963 Dunlap et al 10S-369 3,216,593 11/ 1965 Reuter et al. 213-45 3,236,326 2/ 1966 Reynolds 248-9 X ARTHUR L. LA POINT, Primary Examiner.

F. W. MONAGHAN, D. E. HOFFMAN,

Assistant Examiners. 

3. A BUMPER DEVICE COMPRISING: A BASE PLATE HAVING FIRST AND SECOND SIDES AND A PLURALITY OF TAPERED OPENINGS EXTENDING THERETHROUGH AND TAPERED FROM SMALL ENDS AT THE SECOND SIDE TO RELATIVELY LARGE ENDS AT THE FIRST SIDE; A FLEXIBLE BUMPER OF ELASTOMERIC MATERIAL HAVING AN ABUTMENT PORTION PROJECTING FROM THE SECOND SIDE AND BONDED TO ITS SURFACE, A THIN WAFER PORTION ON THE FIRST SIDE, AND TAPERED ANCHORING STUDS OF THE ELASTOMERIC MATERIAL DIS- 